Luogu4712 WC2006 水管局长 LCT

  1 #include<bits/stdc++.h>
  2 //This code is written by Itst
  3 using namespace std;
  4 
  5 inline int read(){
  6     int a = 0;
  7     bool f = 0;
  8     char c = getchar();
  9     while(c != EOF && !isdigit(c)){
 10         if(c == ‘-‘)
 11             f = 1;
 12         c = getchar();
 13     }
 14     while(c != EOF && isdigit(c)){
 15         a = (a << 3) + (a << 1) + (c ^ ‘0‘);
 16         c = getchar();
 17     }
 18     return f ? -a : a;
 19 }
 20 
 21 const int MAXN = 100010;
 22 vector < pair < int , int > > del[MAXN] , bef[MAXN] , Edge;
 23 struct query{
 24     int type , s , t , w;
 25 }now[MAXN];
 26 struct node{
 27     int ch[2] , fa , maxInd , val;
 28     bool mark;
 29 }Tree[MAXN * 11];
 30 int N , M , Q , cnt , ans[MAXN] , cntAns;
 31 
 32 inline bool nroot(int x){
 33     return Tree[Tree[x].fa].ch[0] == x || Tree[Tree[x].fa].ch[1] == x;
 34 }
 35 
 36 inline bool son(int x){
 37     return Tree[Tree[x].fa].ch[1] == x;
 38 }
 39 
 40 inline int cmp(int a , int b){
 41     return Tree[a].val > Tree[b].val ? a : b;
 42 }
 43 
 44 inline void pushup(int x){
 45     Tree[x].maxInd = cmp(x , cmp(Tree[Tree[x].ch[0]].maxInd , Tree[Tree[x].ch[1]].maxInd));
 46 }
 47 
 48 inline void ZigZag(int x){
 49     bool f = son(x);
 50     int y = Tree[x].fa , z = Tree[y].fa , w = Tree[x].ch[f ^ 1];
 51     if(nroot(y))
 52         Tree[z].ch[son(y)] = x;
 53     Tree[x].fa = z;
 54     Tree[x].ch[f ^ 1] = y;
 55     Tree[y].fa = x;
 56     Tree[y].ch[f] = w;
 57     if(w)
 58         Tree[w].fa = y;
 59     pushup(y);
 60     pushup(x);
 61 }
 62 
 63 inline void pushdown(int x){
 64     if(Tree[x].mark){
 65         Tree[Tree[x].ch[0]].mark ^= 1;
 66         Tree[Tree[x].ch[1]].mark ^= 1;
 67         Tree[x].mark = 0;
 68         swap(Tree[x].ch[0] , Tree[x].ch[1]);
 69     }
 70 }
 71 
 72 void pushdown_all(int x){
 73     if(nroot(x))
 74         pushdown_all(Tree[x].fa);
 75     pushdown(x);
 76 }
 77 
 78 inline void Splay(int x){
 79     pushdown_all(x);
 80     while(nroot(x)){
 81         if(nroot(Tree[x].fa))
 82             ZigZag(son(x) == son(Tree[x].fa) ? Tree[x].fa : x);
 83         ZigZag(x);
 84     }
 85 }
 86 
 87 inline void access(int x){
 88     for(int y = 0 ; x ; y = x , x = Tree[x].fa){
 89         Splay(x);
 90         Tree[x].ch[1] = y;
 91         pushup(x);
 92     }
 93 }
 94 
 95 inline int findroot(int x){
 96     access(x);
 97     Splay(x);
 98     pushdown(x);
 99     while(Tree[x].ch[0])
100         pushdown(x = Tree[x].ch[0]);
101     Splay(x);
102     return x;
103 }
104 
105 inline void makeroot(int x){
106     access(x);
107     Splay(x);
108     Tree[x].mark ^= 1;
109 }
110 
111 inline void split(int x , int y){
112     makeroot(x);
113     access(y);
114     Splay(y);
115 }
116 
117 inline void _link(int x , int y){
118     makeroot(x);
119     Tree[x].fa = y;
120 }
121 
122 inline void cut(int x , int y){
123     split(x , y);
124     Tree[x].fa = Tree[y].ch[0] = 0;
125     pushup(y);
126 }
127 
128 inline void link(int x , int y , int tar){
129     if(findroot(x) == findroot(y)){
130         split(x , y);
131         if(Tree[Tree[y].maxInd].val <= Tree[tar].val)
132             return;
133         int t = Tree[y].maxInd;
134         cut(t , Edge[t - N].first);
135         cut(t , Edge[t - N].second);
136     }
137     _link(x , tar);
138     _link(y , tar);
139 }
140 
141 int main(){
142 #ifndef ONLINE_JUDGE
143     freopen("4172.in" , "r" , stdin);
144     freopen("4172.out" , "w" , stdout);
145 #endif
146     cnt = N = read();
147     M = read();
148     Q = read();
149     for(int i = 1 ; i <= M ; ++i){
150         int a = read() , b = read() , c = read();
151         if(a > b)
152             swap(a , b);
153         bef[a].push_back(make_pair(b , c));
154     }
155     for(int i = 1 ; i <= N ; ++i)
156         sort(bef[i].begin() , bef[i].end());
157     for(int i = 1 ; i <= Q ; ++i){
158         now[i].type = read();
159         now[i].s = read();
160         now[i].t = read();
161         if(now[i].s > now[i].t)
162             swap(now[i].s , now[i].t);
163         if(now[i].type == 2)
164             del[now[i].s].push_back(make_pair(now[i].t , i));
165     }
166     Edge.push_back(make_pair(0 , 0));
167     for(int i = 1 ; i <= N ; ++i){
168         sort(del[i].begin() , del[i].end());
169         int p = 0 , k = del[i].size() , q = bef[i].size();
170         for(int j = 0 ; j < q ; ++j)
171             if(p < k && del[i][p].first == bef[i][j].first)
172                 now[del[i][p++].second].w = bef[i][j].second;
173             else{
174                 Edge.push_back(make_pair(i , bef[i][j].first));
175                 Tree[++cnt].val = bef[i][j].second;
176                 Tree[cnt].maxInd = cnt;
177                 link(i , bef[i][j].first , cnt);
178             }
179     }
180     for(int i = Q ; i ; --i)
181         if(now[i].type == 2){
182             Edge.push_back(make_pair(now[i].s , now[i].t));
183             Tree[++cnt].val = now[i].w;
184             Tree[cnt].maxInd = cnt;
185             link(now[i].s , now[i].t , cnt);
186         }
187         else{
188             split(now[i].s , now[i].t);
189             ans[++cntAns] = Tree[Tree[now[i].t].maxInd].val;
190         }
191     while(cntAns)
192         printf("%d\n" , ans[cntAns--]);
193     return 0;
194 }